Dear colleagues, please find below the abstract and link to our recently published paper on the exceptional occurrence of fossilised baleen in the Miocene cetotheriid Piscobalaena nana: Marx, F.G., Collareta, A., Gioncada, A., Post, K., Lambert, O., Bonaccorsi, E., Urbina, M. & Bianucci, G. 2017 How whales used to filter: exceptionally preserved baleen in a Miocene cetotheriid. *Journal of Anatomy*, published online. Link: http://onlinelibrary.wiley.com/doi/10.1111/joa.12622/full Abstract: Baleen is a comb-like structure that enables mysticete whales to bulk feed on vast quantities of small prey, and ultimately allowed them to become the largest animals on Earth. Because baleen rarely fossilises, extremely little is known about its evolution, structure and function outside the living families. Here we describe, for the first time, the exceptionally preserved baleen apparatus of an entirely extinct mysticete morphotype: the Late Miocene cetotheriid, *Piscobalaena nana*, from the Pisco Formation of Peru. The baleen plates of *P. nana* are closely spaced and built around relatively dense, fine tubules, as in the enigmatic pygmy right whale, *Caperea marginata*. Phosphatisation of the intertubular horn, but not the tubules themselves, suggests in vivo intertubular calcification. The size of the rack matches the distribution of nutrient foramina on the palate, and implies the presence of an unusually large subrostral gap. Overall, the baleen morphology of *Piscobalaena* likely reflects the interacting effects of size, function and phylogeny, and reveals a previously unknown degree of complexity in modern mysticete feeding evolution. Kind regards, Felix Marx _____________________________ *Felix G. Marx* PhD Marie Skłodowska-Curie Postdoctoral Fellow *Royal Belgian Institute of Natural Sciences, Brussels, Belgium *Monash University, Melbourne, Australia *Museum Victoria, Melbourne, Australia Address: School of Biological Sciences, Monash University 18 Innovation Walk, VIC 3800, Australia Tel. +61 (0)3 9905 1190 (Monash University) or +61 (0)3 8341 7346 (Museum Victoria)